What Is Retinopathy of Prematurity?

Retinopathy of prematurity (ROP) is an eye disease that can happen in premature babies. It causes abnormal blood vessels to grow in the retina, and can lead to blindness.

What Happens in ROP?

Retinopathy of prematurity makes blood vessels grow abnormally and randomly in the eye. These vessels tend to leak or bleed, leading to scarring of the retina, the layer of nerve tissue in the eye that lets us see.

When the scars shrink, they pull on the retina, detaching it from the back of the eye. Because the retina is a vital part of vision, its detachment will cause blindness.

What Causes ROP?

During pregnancy, blood vessels grow from the center of a developing baby's retina 16 weeks into the mother's pregnancy, and then branch outward and reach the edges of the retina 8 months into the pregnancy. In babies born prematurely, normal retinal vessel growth may be disrupted and abnormal vessels can develop, which can cause leaking and bleeding into the eye.

ROP has no signs or symptoms when it first develops in a newborn. The only way to detect it is through an eye examination by an ophthalmologist.

How Is ROP Treated?

Some cases of ROP are mild and correct themselves, but others progress to scarring, pulling the retina away from the rest of the eye. These cases require surgery to prevent vision loss or blindness.

ROP surgery stops the growth of abnormal blood vessels. Treatment focuses on the peripheral retina (the sides of the retina) to preserve the central retina (the most important part of the retina). ROP surgery involves scarring areas on the peripheral retina to stop the abnormal growth and eliminate pulling on the retina.

Because surgery focuses on the peripheral retina, some amount of peripheral vision may be lost. However, by preserving the central retina, the eye can still do vital functions like seeing straight ahead, distinguishing colors, reading, etc.

Types of ROP Surgery

The most common methods of ROP surgery are:

laser surgery: This is done most often for ROP. Small laser beams scar the peripheral retina. This procedure (also called laser therapy or photocoagulation) lasts about 30–45 minutes for each eye.

cryotherapy: Freezing temperatures are used to scar the peripheral retina to stop abnormal blood vessel growth. For many years, cryotherapy (also called cryosurgery) was the accepted method of ROP surgery, but it has been all but replaced by laser therapy.

For advanced cases of ROP with retinal detachment, these methods are used:

scleral buckling: This involves placing a flexible band, usually made of silicone, around the circumference of the eye. The band goes around the sclera, or the white of the eye, causing it to push in, or "buckle." This, in turn, pushes the torn retina closer to the outer wall of the eye. This surgery takes 1–2 hours.

vitrectomy: This complex surgery involves replacing the vitreous (the clear gel in the center of the eye) with a saline (salt) solution. This allows for the removal of scar tissue and eases tugging on the retina, which stops it from pulling away. Vitrectomy can take several hours.

Your baby's ophthalmologist will talk with you about which ROP surgery method is best.

What Happens in ROP Surgery?

ROP surgery is usually done with a child under either general anesthesia (medicine that causes a deep sleep-like state) or deep sedation (the patient is unaware of the procedure but not as deeply sedated as with general anesthesia).

Although there is no cutting or stitching involved in laser surgery or cryotherapy, all surgical procedures for ROP require that the baby be given sedation and pain medicine or general anesthesia.

Laser surgery and cryotherapy are usually done at the child's bedside with sedation and pain medicine. Because scleral buckle and vitrectomy surgeries require general anesthesia, they are done in an operating room. For all procedures, the baby's breathing and heart rate is closely watched during the surgery.

Doctors give the baby eye drops to dilate the pupil(s) before the procedure. During the surgery, a tool called an eyelid speculum is gently inserted under the eyelids to keep them from closing.

The eye will be covered with a patch after scleral buckling and vitrectomy, but not after laser surgery or cryotherapy. Whether a hospital stay is required will depend on a child's medical condition and age at the time of surgery.

What Else Should I Know?

If a hospital stay isn't necessary, you can take your child home about an hour after the procedure. Follow-up care for ROP surgery includes giving your child eye drops (to prevent infection) for at least a week.

To make sure the eyes heal properly and that ROP hasn't returned, the ophthalmologist will schedule follow-up eye exams. These are usually every 1–2 weeks. For scleral buckling, the ophthalmologist must examine the buckle every 6 months to account for a child's growing eye.

The goal of ROP surgery is to stop the progression of the disease and prevent blindness. ROP surgery has a good success rate, but not all babies respond to treatment. Up to 25% of babies who have ROP surgery might still lose some or all vision.

With all types of ROP surgery, a degree of peripheral (side) vision will be lost. And even if the ROP stops progressing, vision still can be affected. Because some vision loss and complications can happen, any child who has had ROP surgery should have regular, yearly eye exams well into adulthood.